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| <tr><td width=20><td><b>MEMORY(3)</b><td align=right><b>MEMORY(3)</b> |
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| <p><font size=+1><b>NAME </b></font><br> |
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| memccpy, memchr, memcmp, memcpy, memmove, memset – memory operations<br> |
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| <p><font size=+1><b>SYNOPSIS </b></font><br> |
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| <tt><font size=+1>#include <u.h><br> |
| #include <libc.h> |
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| <tt><font size=+1>void* memccpy(void *s1, void *s2, int c, long n) |
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| <tt><font size=+1>void* memchr(void *s, int c, long n) |
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| </font></tt> |
| <tt><font size=+1>int memcmp(void *s1, void *s2, long n) |
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| <tt><font size=+1>void* memcpy(void *s1, void *s2, long n) |
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| <tt><font size=+1>void* memmove(void *s1, void *s2, long n) |
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| <tt><font size=+1>void* memset(void *s, int c, long n)<br> |
| </font></tt> |
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| <p><font size=+1><b>DESCRIPTION </b></font><br> |
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| These functions operate efficiently on memory areas (arrays of |
| bytes bounded by a count, not terminated by a zero byte). They |
| do not check for the overflow of any receiving memory area. |
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| <i>Memccpy</i> copies bytes from memory area <i>s2</i> into <i>s1</i>, stopping after |
| the first occurrence of byte <i>c</i> has been copied, or after <i>n</i> bytes |
| have been copied, whichever comes first. It returns a pointer |
| to the byte after the copy of <i>c</i> in <i>s1</i>, or zero if <i>c</i> was not found |
| in the first <i>n</i> bytes of <i>s2</i>. |
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| <i>Memchr</i> returns a pointer to the first occurrence of byte <i>c</i> in |
| the first <i>n</i> bytes of memory area <i>s,</i> or zero if <i>c</i> does not occur. |
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| <i>Memcmp</i> compares its arguments, looking at the first <i>n</i> bytes only, |
| and returns an integer less than, equal to, or greater than 0, |
| according as <i>s1</i> is lexicographically less than, equal to, or greater |
| than <i>s2</i>. The comparison is bytewise unsigned. |
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| <i>Memcpy</i> copies <i>n</i> bytes from memory area <i>s2</i> to <i>s1</i>. It returns <i>s1</i>. |
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| <i>Memmove</i> works like <i>memcpy</i>, except that it is guaranteed to work |
| if <i>s1</i> and <i>s2</i> overlap. |
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| <i>Memset</i> sets the first <i>n</i> bytes in memory area <i>s</i> to the value of |
| byte <i>c</i>. It returns <i>s</i>.<br> |
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| <p><font size=+1><b>SOURCE </b></font><br> |
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| All these routines have portable C implementations in <tt><font size=+1>/usr/local/plan9/src/lib9</font></tt>.<br> |
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| <p><font size=+1><b>SEE ALSO </b></font><br> |
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| <a href="../man3/strcat.html"><i>strcat</i>(3)</a><br> |
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| <p><font size=+1><b>BUGS </b></font><br> |
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| ANSI C does not require <i>memcpy</i> to handle overlapping source and |
| destination; on Plan 9, it does, so <i>memmove</i> and <i>memcpy</i> behave |
| identically. |
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| If <i>memcpy</i> and <i>memmove</i> are handed a negative count, they abort.<br> |
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